Various spark-ignition engines include injector assemblies with a prechamber, which is sometimes formed as a separately defined volume from a main combustion chamber to ignite a fuel charge when in use. The prechamber improves combustion characteristics by defining the ignition wave front with apertures formed in the injector tip. The injector tip is sometimes threaded and screwed into the cylinder head to hold it in place. The threads also serve to transfer heat from the injector tip into the cylinder head. Adequate heat transfer acts to mitigate harmful pre-ignition events, such as knocking. However, after extended usage, a threaded injector tip can seize up and become difficult to remove for service. Sometimes a major drilling operation is required to remove the injector assembly from the cylinder head. There exists a continuing need for spark-ignition engine designs to facilitate serviceability of the injector assembly while managing temperature by providing adequate cooling to prevent harmful pre-ignition events.